Which Backup Type to Perform Prior to Installing an OS Patch on a Virtual Server?

A.

The fastest way to restore a server after a patch installation would be to use a snapshot backup.

To determine the backup type that will allow the server to be restored the fastest prior to installing an OS patch on a virtual server, let's examine each option:

A. Snapshot: A snapshot is a point-in-time copy of the virtual machine's disk state. It captures the entire state of the virtual machine, including the OS, applications, and data. When a snapshot is taken, any changes made to the virtual machine after the snapshot will be stored separately. If the patch installation goes wrong or causes issues, the server can be restored to the exact state it was in when the snapshot was taken, eliminating the need to install the patch again. Restoring from a snapshot is generally faster than other backup types since it only involves reverting to a previous disk state. Therefore, option A, Snapshot, is the most likely correct answer.

B. Incremental: Incremental backups involve capturing only the changes made since the last full backup or the last incremental backup. To restore the server to its pre-patch state, the technician would need to restore the last full backup and then apply each subsequent incremental backup in sequence until reaching the desired state. Since the technician needs to install an OS patch, restoring from incremental backups would involve applying the patch again, which may take additional time. Therefore, this option would not allow for the fastest restoration.

C. Differential: Differential backups capture the changes made since the last full backup. Unlike incremental backups, which only capture changes since the last backup, differential backups capture changes since the last full backup regardless of any subsequent incremental backups. To restore the server to its pre-patch state, the technician would need to restore the last full backup and the latest differential backup. Restoring from differential backups may be faster than restoring from incremental backups since it involves fewer backup sets, but it would still require reapplying the OS patch, resulting in additional time.

D. Full: A full backup captures the entire contents of the server, including the OS, applications, and data. To restore the server to its pre-patch state, the technician would need to restore the entire full backup. While a full backup provides a complete copy of the server, it would require additional time to restore since it involves restoring all the data, even if it hasn't changed since the backup was taken.

Considering the above explanations, the most efficient option for restoring the server to its pre-patch state the fastest would be A. Snapshot. By taking a snapshot before the patch installation, the technician can quickly restore the server to its exact state without the need for reapplying the patch or restoring multiple backup sets.